Brand can not be registered with provided email address since duplicate threshold limit has been reached for it.
An email address can not be used multiple times for Sole Proprietor Brand registrations. It is possible that the Starter customer profile bundle used for Sole Proprietor brand registration contains email address which has been used to register one or more Sole Proprietor Brands already.
Please edit the starter customer profile and use a different email address. Once submitted for review, you can resubmit the brand registration request.
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